Short-Flight Ball, and Related Methods

ABSTRACT

A ball comprises a core and a surface that covers the core. The surface includes at least one groove having a depth, a length and a width, wherein the length of the groove is at least three times the width, and wherein the length of the groove extends at most fifty degrees across the surface of the ball. When the ball travels through the air, the groove trips and obstructs the flow of air across the ball&#39;s surface, increasing the air&#39;s drag on the ball. This increase in drag causes the ball to not travel as far as a regular ball when well hit, and opposes any spin imparted to the ball when hit. In addition, the surface of the ball generates a sound that mimics a whistle while air flows across the surface to warn others of the ball&#39;s flight.

BACKGROUND

A traditional golf course covers a distance ranging from about 6,000 to 7,500 yards, or about 3.4 to 4.25 miles, and includes a series of eighteen holes (each ranging in distance from 210-690 yards). A good, experienced golfer (often a professional) can often complete such a course with 72 shots or less because a golf ball is designed to travel far when hit properly. For example, a golf ball is typically very hard and its surface is covered with small, shallow dimples. The hardness of the ball helps the ball convert much of the club head's kinetic energy (primarily the speed at which the club head travels just before impact with the ball) into the ball's kinetic energy (primarily the speed at which the ball travels just after contact with the club head). The small, shallow dimples reduce the air's drag on the ball as the ball travels through the air by tripping the boundary layer of the air flowing over the surface of the ball.

Most golfers, however, cannot complete a traditional golf course with 72 shots or less. Most golfers require significantly more shots because a golf ball that is not hit properly often travels a long distance in the wrong direction. Thus, most courses cover a large area of real estate to accommodate less accurate shots, and most golfers travel about 1.5 times the listed distance of the golf course because they rarely walk straight from each hole's tee to each hole's corresponding green.

To get better, many golfers spend countless hours practicing their swing. Because a regular golf ball travels far when properly hit, golfers can't practice their swing in most urban parks and often go to a driving range that covers a large area to accommodate the long distances that a regular golf ball travels.

To help reduce the size of a golf course and the distance traveled by the average golfer, and to help reduce the size of a driving range, some practice golf balls are designed to travel less distance while in flight compared to a regular golf ball. For example, some golf balls have a smooth surface that significantly increases the air's drag on the golf ball, and some golf balls are softer than a regular golf ball so that less of the club head's kinetic energy is transferred to the ball. Unfortunately, though, these limited-flight golf balls do not provide the same, exciting feel and experience to the golfer as would a regular golf ball when hit properly. The smooth surface of a golf ball adversely affects other flight characteristics of the ball, not just flight distance. And the softness of a golf ball adversely affects the crisp feel of a well hit ball.

SUMMARY

In an aspect of the invention, a ball comprises a core and a surface that covers the core. The surface includes at least one groove having a depth, a length and a width, wherein the length of the groove is at least three times the width, and wherein the length of the groove extends at most fifty degrees across the surface of the ball. When the ball travels through the air, the groove trips and obstructs the flow of air across the ball's surface, increasing the air's drag on the ball. This increase in drag causes the ball to not travel as far as a regular ball when hit, and opposes any spin imparted to the ball when hit.

If the ball is a golf ball, the core may be similar to the core of a regular golf ball to provide the same hardness, and thus the same feel when the ball is hit, while the groove of the surface increases the drag on the golf ball and thus reduces the distance that the golf ball travels in flight. In addition, the surface of the ball generates a sound that mimics a whistle while air flows across the surface to warn others of the ball's flight.

In another aspect of the invention, a cover that can be mounted releasably or fixedly on a ball comprises a body configured to cover a region of the ball. The body has a surface that includes a groove having a depth, a length and a width, wherein the length of the groove is at least three times the width, and wherein the length of the groove extends at most fifty degrees across the surface of the body when the body covers a region of the ball. By covering a region of a ball with the cover, one can reduce the distance that the ball travels when in flight, and one can thus convert any desired ball, such as a baseball, golf ball, and/or softball into a limited-flight ball.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a ball, according to an embodiment of the invention.

FIG. 2 is a perspective view of a groove of the ball shown in FIG. 1, according to an embodiment of the invention.

FIG. 3 is a perspective, partial cross-sectional view of the ball shown in FIG. 1, according to an embodiment of the invention.

FIG. 4 is a flattened view of the whole surface of the ball shown in FIG. 1, according to an embodiment of the invention.

FIG. 5 is a perspective view of a cover for a ball, according to another embodiment of the invention.

Each of FIGS. 6-8 is a view of a surface of a ball, each according to a different embodiment of the invention.

DETAILED DESCRIPTION

FIG. 1 is a perspective view of a ball 10, according to an embodiment of the invention. The ball 10, which may be any desired ball, such as a baseball, tennis ball or golf ball (shown here), includes a surface 12 that covers a core (not shown in FIG. 1 but shown in and discussed in greater detail in conjunction with FIG. 3). The surface 12 includes a groove 14 (here fifty-six but only three labeled for clarity; discussed in greater detail in conjunction with FIG. 2) that has a depth, a length and a width, wherein the length of the groove 14 is at least three times the width, and wherein the length of the groove 14 extends at most fifty degrees across the surface 12. In other embodiments, the surface 12 may be releasably or fixedly mountable to a conventional ball (as discussed in greater detail in conjunction with FIG. 5) to convert the conventional ball into a limited-flight ball.

When the ball 10 is in flight, the groove 14 trips and obstructs the flow of air across the ball's surface, increasing the air's drag on the ball 10. This increase in drag causes the ball 10 not to travel as far as it would without the groove 14. If the ball 10 is a golf ball, then the reduced distance that the ball 10 travels in flight allows one to play golf on a shorter course that does not require walking about 5 to 6.5 miles to complete 18 holes, and/or allows one to practice one's swing in a smaller area. If the ball 10 is a baseball, then the reduced distance allows one to play on a smaller field without the use of a fence or net to confine the ball's flight. The groove 14 also opposes any spin imparted to the ball 10 when hit, which also affects the distance the ball 10 travels in flight.

The surface 12 of the ball 10 may include any desired number of grooves 14 arranged in any desired pattern. For example, in this and other embodiments, the surface 12 includes a plurality of grooves 14 that, together, cover the surface 12 of the ball 10 and are arranged as shown in FIG. 4. More specifically, some of the grooves 14 are disposed longitudinally across the surface 12 of the ball 10, while other grooves 14 are disposed laterally across the surface 12 of the ball 10. In this configuration, the surface 12 generates a sound that mimics a whistle while air flows across the surface 12 to warn others of the ball's flight. In other embodiments, one or more grooves 14 may be arranged to form a serpentine or figure-eight pattern across the surface 12 of the ball 10.

In addition, although each of the grooves 14 shown in FIG. 1 has a length that is at least three times the groove's width and that extends at most fifty degrees across the surface 12 of the ball 10, the surface 12 may include fewer of such grooves 14. In some of such embodiments, the surface 12 may include one or more of such grooves 14 and may also include any number of larger and/or smaller grooves. In other of such embodiments, the surface 12 may include one or more of such grooves 14 and may be smooth for the remainder.

Still referring to FIG. 1, the surface 12 may also include any desired material. For example, in this and other embodiments the surface 12 includes conventional materials that are included in a regular golf ball made according to the official rules of the R&A (Royal and Ancient Golf Club of St Andrew) and/or the USGA (United States Golf Association). More specifically, the surface 12 may include Surlyn®, balata, rubber, and/or urethane. In other embodiments, such as a ball configured for playing baseball or softball, the surface 12 may include leather.

FIG. 2 is a perspective view of a groove 14 of the ball 10 shown in FIG. 1, according to an embodiment of the invention. The groove 14 is defined by one or more walls 16 and a floor 18. Because one or more of the walls 16 of the groove 14 trip and obstruct the flow of air across the ball's surface while the ball 10 travels through air, the size, geometry, and location of each wall 16 relative to another wall 16 of the groove 14 affects the drag that the air imposes on the ball 10 when in flight.

In this and other embodiments, the groove 14 is defined by four walls 16 a, 16 b, 16 c and 16 d that lie perpendicular to each other to form a rectangular groove 14. Moreover, each wall's surface that is exposed to the interior of the groove 14 is convex when viewed from within the groove 14. In other embodiments, the groove 14 may be defined by a single, continuous, curved wall 16 whose end joins with its beginning to form a curved groove such as a circular, elliptical or oblong groove. In addition, the groove 14 may be defined by three walls 16 that intersect each other to form a triangular groove 14. Moreover, one or more of the walls 16 may include a concave or flat interior surface when viewed from within the groove 14. In still other embodiments, the wall 16 may be flattened or may come to a point, and may include ridges to further interact with air when the ball 10 (not shown) travels in flight.

The floor 18 of the groove 14 may also be configured as desired. For example, in this and other embodiments, the floor 18 is rectangular in shape and substantially smooth with a convex curvature that mimics the curvature of the ball 10 (FIG. 1). In other embodiments, the floor 18 may be circular or elliptical in shape, or polygonal such as a trapezoid. In addition, the floor 18 may be concave or flat, and may include bumps or ridges extending up into the interior of the groove 14.

In this and other embodiments, the length 20 of the groove 14 is the distance from the interior surface of the wall 16 a to the interior surface of the wall 16 c. The width 22 of the groove 14 is the distance from the interior surface of the wall 16 d to the interior surface of the wall 16 b. And, the depth 24 is the distance from the plane defined by the tops of each of the walls 16 a-16 d to the floor 18.

Each of the length 20, the width 22, and the depth 24, may be any desired dimension that causes the surface 12 of a ball 10 having the groove 14 to trip and obstruct the flow of air across the surface 12 to increase the air's drag on the ball 10. For example, in this and other embodiments, the depth 24 is at least 0.5 millimeters, and the length 20 is at least three times the width 22 and extends at most fifty degrees across the surface 12. Fifty degrees is the angle θ measured at the center 26 of the ball 10. The angle θ is defined by the intersection of two lines 27 and 28 at the ball's center 26 with line 27 passing through the wall 16 a and line 28 passing through the wall 16 c. More specifically, for the ball 10, several of the grooves 14 extend up to 47 degrees (about 16 millimeters) across the surface 12, while other grooves 14 extend up to 25 degrees (about 9 millimeters) across the surface 12. And for each of the grooves 14, the depth is about 2 millimeters (mm) and the width is about 2 millimeters (mm).

Other embodiments are possible. For example, the length 20 of the groove 14 may be less than three times the width 22, and the depth 24 may be more or less than two millimeters. For another example, a plurality of grooves 14 may include grooves 14 having different depths—the depth 24 of some grooves 14 may be substantially two millimeters (mm) and the depth 24 of other grooves 14 may be substantially three millimeters (mm). For another example, such as a ball 10 that is a baseball, the depth 24 of the groove 14 may be at least 5 millimeters (mm).

FIG. 3 shows a perspective, partial cross-sectional view of the ball 10 shown and discussed in conjunction with FIG. 1, according to an embodiment of the invention. The ball 10 (here a golf ball) includes the surface 12 and a core 30, which is the main source of the ball's conversion of the golf club head's kinetic energy into its own kinetic energy. Thus, the core 30 affects the ball's flight characteristics, and the feel that one perceives when one strikes the ball 10 with a club.

The core 30 may include any desired material arranged in any desired manner that provides a desired hardness. For example, in this and other embodiments, the core 30 is a solid body that includes polybutadiene, a high resiliency rubber composition that may or may not include small pieces of metal, such as tungsten or titanium, distributed throughout the core 30. In other embodiments, the core 30 may include a small, rubber body surrounded by a layer of a different material, such as an elastic material wound around the small body. In such embodiments the small rubber body may be solid or hollow; and if hollow, the body may or may not hold a liquid.

Other embodiments are possible. For example, if the ball 10 is a baseball, then the core 30 may include a rubber or cork body that is wrapped in yarn or string.

FIG. 4 is a flattened view of the whole surface 12 of the ball 10 shown in FIG. 1, according to an embodiment of the invention. Here, the surface 12 of the ball 10 has been divided into two halves 12 a and 12 b to more clearly show the whole surface 12. The surface 12 includes a pattern 13 of grooves 14 (fifty-six grooves are shown here, but only eleven grooves 14 a-14 k have been labeled for clarity).

In this and other embodiments, the pattern 13 includes two symmetrical halves 13 a and 13 b as shown on surface halves 12 a and 12 b, respectively. Each of the symmetrical halves 13 a and 13 b of the pattern 13 includes eight grooves 14 a-14 h (labeled only on pattern half 13 a for clarity) arranged in a square. The eight grooves 14 a-14 h are arranged in alternating pairs, with grooves 14 a, 14 b, 14 e, and 14 f disposed longitudinally on the surface 12 a of the ball, and grooves 14 c, 14 d, 14 h, and 14 g disposed laterally on the surface 12 a of the ball. Each of the two symmetrical halves of the pattern 13 a and 13 b also includes sixteen additional grooves 14 disposed longitudinally across the surface 12 of the ball 10; here only three grooves 14 i-14 k are labeled for clarity. Arranged in this pattern, the grooves 14 significantly increase the air's drag on the ball 10 when the ball travels through the air, which in turn significantly reduces the distance that the ball 10 travels through the air.

Other patterns 13 are possible. For example, see the patterns shown in and discussed in conjunction with FIGS. 6-8.

FIG. 5 is a perspective view of a cover 50 for a ball (not shown), according to another embodiment of the invention. The cover 50 may be sized to be releasably mountable to any specific, desired ball, such as a golf ball, a baseball, or a softball. The cover 50 shown here is sized to be releasably mountable to a golf ball. The cover 50 includes a body 55 having a surface 56 that includes a groove 57 that is similar to the groove 14 shown and discussed in conjunction with FIGS. 1-3. Specifically, the groove 57 has a depth, a width, and a length, the length being at least three times the width, and extending at most fifty degrees across the surface 56. The cover's groove 57 trips and obstructs the flow of air across the cover's surface to increase the air's drag on the cover 50, and thus the drag on the ball to which the cover is mounted. This increase in drag causes the ball to not travel as far as it would without the cover 50 and the cover's groove 57.

In this and other embodiments, the groove 57 does not include a floor in the body 55 of the cover 50. The floor is formed by the outer surface of the ball after the cover 50 is mounted to the ball. In other embodiments, the groove 57 does include a floor in the body 55 of the cover 50.

The cover 50 may be releasably mounted to a ball in any desired manner. For example, in this and other embodiments the body 55 of the cover 50 includes an opening 58 that one inserts the ball through to surround the ball with the cover 50. In such embodiments, the opening 58 may be a slit, and the body 55 may be elastic and sized to exert a compressive force on the ball when the cover 50 is mounted to the ball. In other embodiments, the body 55 may not be elastic and the opening 58 may be larger and include any desired fastening mechanism (not shown), such as Velcro® and/or laces to keep the cover 50 on the ball after the ball is hit.

The cover 50 may be configured to cover any desired portion of a ball. For example, in this and other embodiments, the cover 50 surrounds the ball. In other embodiments, however, the cover 50 may cover a region or a portion of a ball, such as half, three quarters or one third of the whole surface of the ball.

Still referring to FIG. 5, the body 55 may include any desired material. For example, in this and other embodiments the body 55 may include natural or synthetic rubber, urethane, and/or other plastic or elastic materials.

Each of FIGS. 6-8 shows a view of a surface of one of a respective three balls, each according to a different embodiment of the invention. The surface of each of the balls includes a groove that is similar to the groove 14 (FIG. 2) previously discussed—i.e. the groove includes a depth, a width and a length that is at least three times the width and extends at most fifty degrees across the surface 12.

FIG. 6 shows a ball 60 whose surface 65 includes sixty-eight grooves 66 (forty-eight shown but only five labeled for clarity) each of which is substantially oval shaped and arranged in the pattern shown. Although half of the ball 60 is not shown in FIG. 6, the pattern of the un-seen half is identical to the pattern shown. Arranged in this pattern, the grooves 66 provide substantial drag to the ball 60 that significantly reduces the distance that the ball 60 will travel in flight.

FIG. 7 shows a ball 70 whose surface 75 includes eighty-four grooves 76 (sixty shown but only five labeled for clarity) each of which being substantially oval shaped and arranged in the pattern shown. Although half of the ball 70 is not shown in FIG. 7, the pattern of the un-seen half is identical to the pattern shown. Arranged in this pattern, the grooves 76 also provide substantial drag to the ball 70 that significantly reduces the distance that the ball 70 will travel in flight, and the surface 75 may be expanded to cover a larger ball such as a baseball.

FIG. 8 shows a ball 80 whose surface 85 includes sixty-four grooves 86 (thirty-two shown but only five labeled for clarity) each of which is serpentine in shape and arranged in the pattern shown. Although half of the ball 80 is not shown in FIG. 8, the pattern of the un-seen half is identical to the pattern shown. Arranged in this pattern, the grooves 85 also provide substantial drag to the ball 80 that significantly reduces the distance that the ball 80 will travel when well hit.

The preceding discussion is presented to enable a person skilled in the art to make and use the invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the generic principles herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. 

1. A ball, comprising a core having a center; and a surface that covers the core, and includes a groove having a depth, a length and a width, wherein: the length of the groove is at least three times the width, the length of the groove extends at most fifty degrees across the surface relative to the core's center, and the depth of the groove is at least two millimeters (mm).
 2. The ball of claim 1 wherein the ball is a golf ball.
 3. The ball of claim 1 wherein the core is solid.
 4. The ball of claim 1 wherein the core includes a liquid.
 5. The ball of claim 1 wherein the surface completely covers the core.
 6. The ball of claim 1 wherein the surface includes two symmetrical halves.
 7. The ball of claim 1 wherein the surface includes at least two grooves.
 8. The ball of claim 1 wherein the groove includes two parallel sides.
 9. The ball of claim 1 wherein the groove includes four sides that form a quadrilateral shape.
 10. The ball of claim 1 wherein the groove includes a floor that is curved.
 11. The ball of claim 1 wherein the surface generates a sound that mimics a whistle while air flows across the surface.
 12. A ball, comprising: a core; and a surface that covers the core, and includes a groove having a depth, a length and a width, wherein the depth of the groove is at least two millimeters (mm).
 13. The ball of claim 12 wherein the ball is a golf ball.
 14. The ball of claim 12 wherein the groove includes two parallel sides.
 15. The ball of claim 12 wherein the surface includes at least two grooves.
 16. The ball of claim 12 wherein the groove includes a floor that is curved.
 17. A method for limiting the flight of a ball, the method comprising: disrupting the flow of air across a surface of a ball with a wall of a groove disposed on the surface, the ball having a center, and the groove having a depth, a length and a width, wherein: the length is at least three times the width, the length extends at most fifty degrees across the surface of the ball relative to the ball's center, and the depth of the groove is at least two millimeters (mm).
 18. A cover for a ball, the cover comprising: a body configured to cover a region of a ball, the body having a center and a surface that includes a groove, the groove having a depth, a length and a width, wherein: the length of the groove is at least three times the width, the length of the groove extends at most fifty degrees across the surface of the body relative to the body's center when the body covers a region of the ball, and the depth of the groove is at least two millimeters (mm).
 19. The cover of claim 18, wherein the body is elastic.
 20. The cover of claim 18, wherein the body is configured to surround the ball.
 21. The cover of claim 18, wherein the body includes an opening to permit the body to be slipped over the ball, and the body is configured to hold the ball after the ball passes through the opening.
 22. The cover of claim 18, wherein the groove includes a floor.
 23. The cover of claim 18, wherein the body includes at least two grooves. 